I grabbed this 10" fan at Wally World today to check it out. It is an Ozark Trail portable camping fan. Supposed to run on 8 D batteries (12 volts). I connected a 12 volt plug to it for a test. It works absolutely great. Has 2 speeds and is not loud at all yet moves plenty of air on either speed. It folds for storage or hanging in front of a window or sets on it's base. It could also be mouted sideways on a wall and folded out of the way when not in use.
I checked the current draw with a digital meter and it draws .46A on low and .65A on high. I was impressed. I was going to use computer fans but this is way better.
Best part: $13.88.
EZ